The teenager behind a "Kick a Ginger" group on Facebook is being investigated by police after reports of attacks on redhead children.

Nearly 5,000 people joined the online campaign which urged members to "get them steel toes ready" for a day of booting this week.

The website appears to have been inspired by a recent episode of the cartoon South Park, in which a young character called Cartman describes people with red hair as evil and soulless.

Dozens of children left messages on the page claiming to have carried out attacks on "National Kick a Ginger Day" on Thursday, and a girl in Alberta, Canada claimed that she and her 13-year-old sister were punched and kicked by pupils at their school.

The 14-year-old boy from Vancouver who ran the Facebook group has apologised and insisted that it was only meant as a joke, but the Royal Canadian Mounted Police has launched an investigation and warned that those involved could face charges.

"We do treat this sort of thing seriously," a police spokeswoman told the Vancouver Sun newspaper.

"This is sort of inciting hate. It's a hate crime, really."

Some Canadian schools had appealed to students not to take the Facebook group seriously, as word of the campaign spread across the country.

Ironically, National Kick a Ginger Day fell during Canada's bullying awareness week.